Environmental Issues




Current environmental issues for the Samoans are soil erosion, deforestation, invasive species, overfishing. Soil erosion is Soil being washed off the islands and deposited in the lagoon is a problem facing both Samoa and American Samoa. The construction of roads and development of new housing too close to the shoreline are two causes which have been cited. In Savai'i logging of virgin primary forest has also contributed to this problem. With the trees and their root systems removed there is nothing to hold the soil in place when it rains. As well leading to increased sedimentation over the reef and a reduction in the amount of light available for photosynthesis by the algal symbiants in the coral it also causes unprecedented amounts of nutrients to be introduced into the lagoon. The nutrients encourage certain types of alga to reproduce very rapidly leading to the formation of surface scum and severe reductions in oxygen levels in the water within the lagoon which causes many of the marine animals to die. Deforestation is the rapidly cutting down of trees in a forest to a point where the forest could no longer exist. Samoa faces a major environmental threat from deforestation. Agricultural change is the major culprit although logging has played its part in disturbing the delicate ecosystem. Marine resources are also under pressure from over-fishing, the gung-ho practice of blowing fish out of the water with explosives, and a deadly increase in the reef-wrecking crown-of-thorns starfish. Fortunately there has been a concerted effort over the last few years to develop eco-friendly industries and conserve the beauty and biological diversity of the rain forests that cover much of the uplands. Invasive species are any plant, animal or virus which is not often originally from Samoa and is spreading beyond its normal occurrence rate causing a menace to agriculture or personal resources by damaging it. Invasive species are recognized as highly adaptive and fast breeding organisms. They are able spread freely in any particular environment, and due to their ability to breed uncontrollably; invasive species have an adverse influence on both humans and the environment. Their interference with the environment has resulted in serious destruction and is a case that should be taken seriously in Samoa. Invasive vines such as merremia overwhelm vast areas of the native forests in Samoa driving many of our local plants to the verge of extinction. Furthermore, invasive vines also cause the production of flowers and fruits to dramatically decrease, affecting the species which depend on these fruits for food. Such examples include pigeons and fruit-bats. Such impacts on the environment can also affect the people living in Samoa by creating enormous costs to our islands development, food security, and human livelihoods through the damage and ruin caused to our agriculture, fisheries, and forestry industries. Moreover, Invasive species are also known to be disease carriers, thus directly harming humans and their health. Samoa has no known established population of the mongoose, but the animals are common in Hawaii and Fiji, having been introduced to control the rats that were damaging the sugar cane fields. Despite this, mongooses do not reduce rat damage, and the IUCN (International Union for the Conservation of Nature) lists the mongoose as one of the 100 worst invasive species because of the impact it has on native birds and animals. In Fiji, it is considered the main cause behind the extinction of several bird species on Viti Levu, the largest island.The first report of a mongoose in Samoa was in December last year, when a conservation team working on another project happened to see a mongoose crossing the road. After much consultation with surrounding villagers it appeared that the mongoose had been sighted as far back as 2008. Samoa is no stranger to the damages that an invasive species can cause. In 1993 a taro leaf blight outbreak devastated the staple crop decimating farmers' incomes from both the local and overseas markets. Finally, there is overfishing.
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Many marine ecologists think that the biggest single threat to marine ecosystems today is overfishing. Our appetite for fish is exceeding the oceans' ecological limits with devastating impacts on marine ecosystems. Scientists are warning that overfishing results in profound changes in our oceans, perhaps changing them forever. Not to mention our dinner plates, this in future may only feature fish and chips as a rare and expensive delicacy. Two types of fisheries harvest the park’s coral reef fishes and invertebrates--subsistence fishing by villagers (usually shoreline activities with gear, such as rod and reel, spears, gillnet, or gleaning, or small-boat fishermen who jig for bottomfish around the steeply sloping islands, and whose fish are mostly sold at local stores. A trend in these coral reef fisheries is that species such as giant clams and parrotfish are overfished, and there has long been heavy fishing pressure on surgeonfish. There are fewer and/or smaller groupers, snappers and jacks. Few fish larger than 16 inches in length are found on the park’s reefs. The “no large fish” attribute has huge ecological implications. Loss of larger fish means a tremendous loss of spawning potential—consider, one large female red snapper (61 cm) has the spawning potential of 212 smaller females (42 cm). And with life history patterns that mortality of young is extremely high--a fish has to live and spawn for decades in order to insure that at least a few of its juveniles successfully make it back to a reef and grow to maturity. With the number of spawners reduced to a skeleton population through overfishing Samoa’s reefs are at a point where production of larvae and subsequent recruitment are greatly impaired. Given the very slow growth of reef fishes, and their normal long life expectancy when not fished, for even a chance to restore a large fish component of the park’s reefs will require decades’ relief from overfishing.